The invention relates to a seal arrangement for a gas turbine.
Gas turbines consist of several assemblies, for example, of a fan, a combustion chamber, preferably several compressors, as well as several turbines. The preferably several turbines are, in particular, a high-pressure turbine, as well as a low-pressure turbine; the several compressors are, in particular, a high-pressure compressor and a low-pressure compressor.
Considering a turbine, as well as a compressor of a gas turbine, several guide vane rings are positioned in series in the axial direction or in the direction of flow of the gas turbine, in which case each guide vane ring has several circumferentially arranged guide vanes. Positioned between each two adjacent guide vane rings is one rotor blade ring having several rotor blades. The rotor blades are associated with a rotor and rotate together with the rotor relative to a stationary housing, as well as relative to the also stationary guide vanes of the guide vane rings.
In order to optimize the degree of efficiency of a gas turbine, it is necessary to avoid any leakage between the rotating rotor blades and the stationary housing, on one hand, and between the stationary guide vanes and the rotor, on the other hand, by using effective sealing systems. Prior art has already disclosed the use of special intake linings for sealing the gap between the radially external ends of the rotor blades and the stationary housing, in which case the intake linings are applied to the stationary housing in order to permit a wear-free gentle moving contact of the radially external ends of the rotating rotor blades into the intake lining. Furthermore, prior art has disclosed seal arrangements, which are used to seal a gap between the radially internal ends of the stationary guide vanes and the rotor of the gas turbine, the seal arrangements being configured in such a manner that the rotor comprises at least two seal projections extending in the circumferential direction of the rotor and being positioned at an axial distance from each other, the seal projections communicating with the intake linings that are associated with the radially internal ends of the stationary guide vanes.
The present invention relates to a seal arrangement for sealing the gap between radially internal ends of the guide vanes of a guide vane ring and a rotor of the gas turbine.
Considering this, the object of the invention is to provide a novel seal arrangement for a gas turbine.
In accordance with the invention, the seal projections are inclined or tilted in the axial direction toward a side of higher pressure, whereby, in a space limited by the minimum of two seal projections and the corresponding intake linings, at least one recirculation structure is provided, and whereby the recirculation structure, or the recirculation structures, is or are oriented toward the side of the higher pressure.
In accordance with an advantageous development of the invention, the seal projections are configured as seal fins and the intake linings are configured as honeycomb structures.
Preferably, the seal projections, which communicate with a guide vane ring, and the corresponding intake linings of the guide vane ring have different radii, in which case the outer radii of the seal projections, as well as the inner radii of the intake linings, increase or become greater in the direction toward the side of the higher pressure.